Title :
Improvement of Return Loss Bandwidth of Balanced Amplifier Using Metamaterial-Based Quadrature Power Splitters
Author :
Tseng, Chao-Hsiung ; Chang, Chih-Lin
Author_Institution :
Nat. Taiwan Univ. of Sci. & Technol., Taipei
fDate :
4/1/2008 12:00:00 AM
Abstract :
A new balanced amplifier (BA) using metamaterial-based quadrature power splitters (QPSs) is presented in this letter. Instead of using conventional 90 couplers, the developed BA is implemented by two parallel amplifiers with broadband metamaterial-based QPSs at input and output ends. Since the QPSs can provide a broadband quadrature phase difference between two outputs, the input/output reflections from two amplifiers can be effectively cancelled over a wide bandwidth. The developed BA demonstrates the input/output return loss of better than 10 dB from 1.2 to 3.5 GHz with 97.9% relative bandwidth.
Keywords :
differential amplifiers; metamaterials; optical beam splitters; waveguide couplers; wideband amplifiers; balanced amplifier; broadband quadrature; metamaterial-based quadrature power splitters; parallel amplifiers; return loss bandwidth; Balanced amplifiers (BAs); broadband amplifiers; metamaterials (MMs); quadrature power splitters (QPS);
Journal_Title :
Microwave and Wireless Components Letters, IEEE
DOI :
10.1109/LMWC.2008.918914